docs: backfill XML documentation across 756 files

Adds <summary>, <param>, <typeparam>, and <inheritdoc/> tags to public
members surfaced by commentchecker — resolves 5,847 of 5,869 issues
(99.6%) across three /fixdocs passes.

tests/Core/ZB.MOM.WW.OtOpcUa.Configuration.Tests/NodePermissionsTests.cs

@@ -13,6 +13,7 @@ namespace ZB.MOM.WW.OtOpcUa.Configuration.Tests;
 [Trait("Category", "Unit")]
 public sealed class NodePermissionsTests
 {
+    /// <summary>Verifies that the underlying type is int so it matches HasConversion in DbContext.</summary>
     [Fact]
     public void Underlying_type_is_int_so_it_matches_HasConversion_in_DbContext()
     {
@@ -22,6 +23,7 @@ public sealed class NodePermissionsTests
         typeof(NodePermissions).GetEnumUnderlyingType().ShouldBe(typeof(int));
     }
 
+    /// <summary>Verifies that all defined bits round trip through int cast without loss.</summary>
     [Fact]
     public void All_defined_bits_round_trip_through_int_cast_without_loss()
     {
@@ -35,6 +37,7 @@ public sealed class NodePermissionsTests
         }
     }
 
+    /// <summary>Verifies that bitwise combinations round trip through int storage.</summary>
     [Fact]
     public void Bitwise_combinations_round_trip_through_int_storage()
     {